Bonding is further complicated when the baby and mother are separated. In some cases the ill newborn may be transferred to a high-risk perinatal centre at another hospital leaving the separated mother surrounded by new mothers and their infants, marooned empty-armed and bewildered in the maternity unit geared to breastfeeding and baby-routines. Other parents may benefit from joining a self-help group of bereaved parents who have experienced a perinatal death, such as the Stillbirth and Neonatal Death Society or Parents Experiencing Neonatal Death. The higher incidence of hearing loss in very low birth weight infants has been attributed to synergistic effects of noise exposure and retinopathy of prematurity has been associated with unfiltered light and sunlight. The long-term emotional effects of prematurity and incubation are methodically very complex to tease out. Professionals working with severely ill neonates are under great deal of pressure which has been found to lead to a 'burnout' syndrome of low morale, stress-related illnesses and absenteeism.